The Trump administration has approved the sale of F-35 fighter jets to Saudi Arabia, a move that would bolster the Gulf ally’s military.

The US State Department announced the proposed sale of the most advanced American fighter jet – the Lightning II Joint Strike Fighter Aircraft - and related equipment, worth an estimated $24.3 billion, according to a statement on Thursday.

Saudi Arabia is a major purchaser of US weapons, including F-15 fighter jets, and the Gulf state has long sought to join the F-35 program.

However, the sale still needs approval from Congress, where some members are wary of deepening military cooperation with Saudi Arabia given the kingdom’s ties to China. Even if the sale is approved, delivery of the fighter jets would be years away.